When using the Email Designer in ACS, editing the preheader is a rather unintuitive task. Clicking 'just the right spot' between whatever structures you have in an email and the menu to the right to make the preheader field appear can be pretty tedious - especially since many of my colleagues use MS surface devices and the like (many 11" - 13" devices). It'd be great with a more easily accessible way to edit the preheader.
I'd like to propose moving the preheader field into the section where the subject line currently resides. Since most users associate the subject line and preheader with each other, this would be a much more intuitive way of editing an email delivery.